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951.
Phase behaviour of nematic liquid crystals (N‐(p‐ethoxybenzylidene)‐p‐butylaniline and N‐(p‐methoxybenzylidene)‐p‐butylaniline) in linear polystyrene are investigated by thermo‐optical analysis. Results are compared to the model based on the extended Flory‐Huggins equation. The model used in this work includes two adjustable model parameters (d0, d1). The proposed semi‐empirical model gives a very good agreement with new data obtained for liquid crystal and polystyrene systems. 相似文献
952.
Azide moieties, unique linear species containing three nitrogen atoms, represent an attractive class of molecular tag for hyperpolarized magnetic resonance imaging (HP-MRI). Here we demonstrate (15N)3-azide-containing molecules exhibit long-lasting hyperpolarization lifetimes up to 9.8 min at 1 T with remarkably high polarization levels up to 11.6% in water, thus establishing (15N)3-azide as a powerful spin storage for hyperpolarization. A single (15N)-labeled azide has also been examined as an effective alternative tag with long-lived hyperpolarization. A variety of biologically important molecules are studied in this work, including choline, glucose, amino acid, and drug derivatives, demonstrating great potential of 15N-labeled azides as universal hyperpolarized tags for nuclear magnetic resonance imaging applications.This work demonstrates that 15N-labeled azides are practical and effective tags for developing long-lived hyperpolarized MRI agents and can offer hyperpolarization lifetimes up to 9.8 min at 1 T and high polarization levels up to 11.6% in water. 相似文献
953.
Ramanaskanda Braveenth Keunhwa Kim Il-Ji Bae Kanthasamy Raagulan Bo Mi Kim Miyoung Kim Kyu Yun Chai 《Molecules (Basel, Switzerland)》2021,26(24)
Two small molecular hole-transporting type materials, namely 4-(9,9-dimethylacridin-10(9H)-yl)-N-(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-N-phenylaniline (TPA-2ACR) and 10,10′-(9-phenyl-9H-carbazole-3,6-diyl)bis(9,9-dimethyl-9,10-dihydroacridine) (PhCAR-2ACR), were designed and synthesized using a single-step Buchwald–Hartwig amination between the dimethyl acridine and triphenylamine or carbazole moieties. Both materials showed high thermal decomposition temperatures of 402 and 422 °C at 5% weight reduction for PhCAR-2ACR and TPA-2ACR, respectively. TPA-2ACR as hole-transporting material exhibited excellent current, power, and external quantum efficiencies of 55.74 cd/A, 29.28 lm/W and 21.59%, respectively. The achieved device efficiencies are much better than that of the referenced similar, 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC)-based device (32.53 cd/A, 18.58 lm/W and 10.6%). Moreover, phenyl carbazole-based PhCAR-2ACR showed good device characteristics when applied for host material in phosphorescent OLEDs. 相似文献
954.
Sul Ki Park Puritut Nakhanivej Jeong Seok Yeon Kang Ho Shin Wesley M.Dose Michael De Voider Jin Bae Lee Hae Jin Kim Ho Seok Park 《Journal of Energy Chemistry》2021,(4):108-113
With the development of stable alkali metal anodes,V2O5 is gaining traction as a cathode material due to its high theoretical capacity and the ability to intercalate Li,Na and K ions.Herein,we report a method for synthesizing structured orthorhombic V2O5 microspheres and investigate Li intercalation/deintercalation into this material.For industry adoption,the electrochemical behavior of V2O5 as well as structural and phase transformation attributing to Li intercalation reaction must be further investigated.Our synthesized V2O5 microspheres consisted of small primary particles that were strongly joined together and exhibited good cycle stability and rate capability,triggered by reversible volume change and rapid Li ion diffusion.In addition,the reversibility of phase transformation(a,e,d,c and xLixV2O5)and valence state evolution(5+,4+,and 3.5+)during intercalation/de-intercalation were studied via in-situ X-ray powder diffraction and X-ray absorption near edge structure analyses. 相似文献
955.
956.
Han Su Cheol Park Woon Bae Sohn Kee-Sun Pyo Myoungho 《Journal of Solid State Electrochemistry》2019,23(11):3135-3143
Journal of Solid State Electrochemistry - KFeO2 is presented as a new type of cathode material for potassium-ion batteries. In contrast to LiFeO2 and NaFeO2, KFeO2 has tetrahedrally coordinated... 相似文献
957.
Eun-Jin Bae Na Young Yang Cheolsoon Lee He-Jin Lee Seokjoong Kim Sergio Pablo Sardi Seung-Jae Lee 《Experimental & molecular medicine》2015,47(3):e153
Lysosomal dysfunction is a common pathological feature of neurodegenerative diseases. GTP-binding protein type A1 (GBA1) encodes β-glucocerebrosidase 1 (GCase 1), a lysosomal hydrolase. Homozygous mutations in GBA1 cause Gaucher disease, the most common lysosomal storage disease, while heterozygous mutations are strong risk factors for Parkinson''s disease. However, whether loss of GCase 1 activity is sufficient for lysosomal dysfunction has not been clearly determined. Here, we generated human neuroblastoma cell lines with nonsense mutations in the GBA1 gene using zinc-finger nucleases. Depending on the site of mutation, GCase 1 activity was lost or maintained. The cell line with GCase 1 deficiency showed indications of lysosomal dysfunction, such as accumulation of lysosomal substrates, reduced dextran degradation and accumulation of enlarged vacuolar structures. In contrast, the cell line with C-terminal truncation of GCase 1 but with intact GCase 1 activity showed normal lysosomal function. When α-synuclein was overexpressed, accumulation and secretion of insoluble aggregates increased in cells with GCase 1 deficiency but did not change in mutant cells with normal GCase 1 activity. These results demonstrate that loss of GCase 1 activity is sufficient to cause lysosomal dysfunction and accumulation of α-synuclein aggregates. 相似文献
958.
Hyeong-Ohk Bae 《Journal of Differential Equations》2018,264(7):4889-4900
The regularity of 2D Navier–Stokes flow is well known. In this article we study the relationship of 3D and 2D flow, and the regularity of the 3D Naiver–Stokes equations with viewpoint of 2D equations. We consider the problem in the Cartesian and in the cylindrical coordinates. 相似文献
959.
Guang‐Ri Xu Y. P. Zhang Jian Zhong Tao Sunghyun Kim Zun‐Ung Bae 《Electroanalysis》2007,19(10):1085-1092
In this paper, we describe the double modification of the glassy carbon electrode surface with two polymer layers for the selective determination of dopamine. The first layer was the electropolymerized macrocyclic nickel complex acting as an electrocatalyst for the dopamine oxidation and the second layer the polyurethane benzyl L ‐glutamate (PUBLG) for screening interfering species. Hydrolyzed PUBLG (PU‐C) showed a better screening effect. Thus prepared GC/Ni(II) complex film/PU‐C electrodes exhibited improved selectivity and better performance than unmodified counterparts, with minimum passivation even in the presence of large excess of interferents. Under optimal conditions, these electrodes showed a linear response over a dopamine concentration range of 2.5×10?7 and 3.0×10?5 M with a correlation coefficient of 0.999 and detection limit (at S/N=3) of 8.0×10?8 M. The recoveries of dopamine in the 5‐fold diluted human urine sample were 96.9% for 4 measurements. The rate constant for the dopamine oxidation measured by the rotating disk electrode was found to be 1.1×10?3 cm s?1. 相似文献
960.
Yu-Rim Song Boyun Jang Sung-Min Lee Su-Jin Bae Seon-Been Bak Young-Woo Kim 《Molecules (Basel, Switzerland)》2022,27(6)
Natural products and medicinal herbs have been used to treat various human diseases by regulating cellular functions and metabolic pathways. Angelica gigas NAKAI (AG) helps regulate pathological processes in some medical fields, including gastroenterology, gynecology, and neuropsychiatry. Although some papers have reported its diverse indications, the effects of AG against arachidonic acid (AA)+ iron and carbon tetrachloride (CCl4) have not been reported. In HepG2 cells, AA+ iron induced cellular apoptosis and mitochondrial damage, as assessed by mitochondrial membrane permeability (MMP) and the expression of apoptosis-related proteins. On the other hand, AG markedly inhibited these detrimental phenomena and reactive oxygen species (ROS) production induced by AA+ iron. AG activated the liver kinase B1 (LKB1)-dependent AMP-activated protein kinase (AMPK), which affected oxidative stress in the cells. Moreover, AG also regulated the expression of yes-associated protein (YAP) signaling as mediated by the AMPK pathways. In mice, an oral treatment of AG protected against liver toxicity induced by CCl4, as indicated by the plasma and histochemical parameters. Among the compounds in AG, decursin had antioxidant activity and affected the AMPK pathway. In conclusion, AG has antioxidant effects in vivo and in vitro, indicating that natural products such as AG could be potential candidate for the nutraceuticals to treat various disorders by regulating mitochondrial dysfunction and cellular metabolic pathways. 相似文献